I have a strange problem with my system. For some reasons, after couple of days my internet connectivity stops working and i am not able to browse or ping any server. If i disconnect my wifi and reconnect then it starts working again for couple of minutes and then stops working. The problem arises with all the browsers that i have. When my browsing stops, any other application (mainly torrent) that is using the internet keeps on working, so if i am downloading something it will keep on downloading but the rest would stop.